Home is best if we're talking about pooping. A friend's place is great, too, if you don't tell them and watch their reaction as they walk in there after you unsuspectingly. Ha-ha, Gotcha!
Luckily when I was still working, most of the places had a nice clean bathroom. Like @wascaptain says, most anything beats shittin' in: a plastic bag, 5 gal bucket, communal asian squat toilets, a busy Porta Potty that hasn't been cleaned in 2 weeks or the woods